1/6/20, 3:42:22 PM
Compare Results
New File:
Old File:
First Aid for the USMLE Step 1 2020, Thirtieth
FA 2019.pdf
versus edition-1.pdf
64 pages (293.11 MB)
64 pages (109.99 MB)
1/5/20, 12:57:57 PM
1/5/20, 12:52:18 PM
BY u/verified-idiot
To the only girl i've ever loved, to soufia.
BLUE new in FA 2020
YELLOW text of FA 2019 was edited; the note box next to the yellow highlight will show
the difference between them the old text and the new text of FA 2020
Some pages might look scary! because of note boxes and highlighting , but it is not, my
recommendation for you is to study your book and after than look for the new stuff and
edits.. I DONT recommend comparing while you are studying since it will consume your
time.
Go to First Change (page 1)
file://NoURLProvided[1/6/20, 3:42:22 PM]
,HIGH-YIELD SYSTEMS
Neurology and
Special Senses
“We are all now connected by the Internet, like neurons in a giant brain.” ` Embryology 490
—Stephen Hawking
` Anatomy and
“Anything’s possible if you’ve got enough nerve.” Physiology 493
—J.K. Rowling, Harry Potter and the Order of the Phoenix
` Pathology 511
“I like nonsense; it wakes up the brain cells.”
—Dr. Seuss ` Otology 533
“I believe in an open mind, but not so open that your brains fall out.”
` Ophthalmology 534
—Arthur Hays Sulzberger
“The chief function of the body is to carry the brain around.” ` Pharmacology 544
—Thomas Edison
“Exactly how [the brain] operates remains one of the biggest unsolved
mysteries, and it seems the more we probe its secrets, the more surprises we
find.”
—Neil deGrasse Tyson
Understand the difference between upper motor neuron (UMN) and
lower motor neuron (LMN) findings and the underlying anatomy.
Know the major motor, sensory, cerebellar and visual pathways and their
respective locations in the CNS. Connect key neurological associations
with certain pathologies (eg, cerebellar lesions, stroke manifestations,
Brown-Séquard syndrome). Recognize common findings on MRI/
CT (eg, ischemic and hemorrhagic stroke) and on neuropathology
(eg, neurofibrillary tangles and Lewy bodies). High-yield medications
include those used to treat epilepsy, Parkinson disease, migraine, and
pain (eg, opioids).
489
,490 SEC TION III NEUROLOGY AND SPECIAL SENSES `ǸEUROLOGY—EMBRYOLOGY
``
NEUROLOGY—EMBRYOLOGY
Neural development Notochord induces overlying ectoderm to differentiate into neuroectoderm and form neural plate.
Neural plate Neural plate gives rise to neural tube and neural crest cells.
Day 18 Notochord becomes nucleus pulposus of intervertebral disc in adults.
Notochord
Neural fold Alar plate (dorsal): sensory; regulated by TGF-β
(including bone morphogenetic protein [BMP])
Same orientation as spinal cord
Basal plate (ventral): motor; regulated by
Neural tube
Neural sonic hedgehog gene (SHH)
crest
cells
Day 21
Regional specification Telencephalon is the 1st part. Diencephalon is the 2nd part. The rest are arranged alphabetically:
of developing brain mesencephalon, metencephalon, myelencephalon.
Three primary Five secondary Adult derivatives of:
vesicles vesicles Walls Cavities
Telencephalon Cerebral Lateral
Wall Cavity hemispheres ventricles
Basal ganglia
Forebrain Diencephalon Thalamus Third
(prosencephalon) Hypothalamus ventricle
Retina
Midbrain Mesencephalon Midbrain Cerebral
(mesencephalon) aqueduct
Pons Upper part of
fourth ventricle
Metencephalon
Hindbrain Cerebellum
(rhombencephalon)
Myelencephalon
Medulla Lower part of
fourth ventricle
Spinal cord
Central and peripheral Neuroepithelia in neural tube—CNS neurons, ependymal cells (inner lining of ventricles, make
nervous systems CSF), oligodendrocytes, astrocytes.
origins Neural crest—PNS neurons, Schwann cells, glia, melanocytes, adrenal medulla.
Mesoderm—Microglia (like Macrophages).
, NEUROLOGY AND SPECIAL SENSES `ǸEUROLOGY—EMBRYOLOGY SEC TION III 491
Neural tube defects Neuropores fail to fuse (4th week) persistent connection between amniotic cavity and spinal
canal. Associated with maternal diabetes and folate deficiency. α-fetoprotein (AFP) in amniotic
fluid and maternal serum (except spina bifida occulta = normal AFP). acetylcholinesterase
(AChE) in amniotic fluid is a helpful confirmatory test.
Spina bifida occulta Failure of caudal neuropore to close, but no herniation. Usually seen at lower vertebral levels. Dura
is intact. Associated with tuft of hair or skin dimple at level of bony defect.
Meningocele Meninges (but no neural tissue) herniate through bony defect.
Myelomeningocele Meninges and neural tissue (eg, cauda equina) herniate through bony defect.
Myeloschisis Also called rachischisis. Exposed, unfused neural tissue without skin/meningeal covering.
Anencephaly Failure of rostral neuropore to close no forebrain, open calvarium. Clinical findings:
polyhydramnios (no swallowing center in brain).
+/ Tuft of hair Skin defect/thinning Skin thin or absent
Skin +/ Skin dimple
Subarachnoid
space
Dura
Leptomeninges
Spinal Transverse
cord process
Normal Spina bifida occulta Meningocele Myelomeningocele
Holoprosencephaly Failure of the embryonic forebrain (prosencephalon) to separate into 2 cerebral hemispheres;
A
usually occurs during weeks 5–6. May be related to mutations in sonic hedgehog signaling
pathway. Associated with other midline defects including cleft lip/palate (moderate form) and
★ cyclopia (severe form). risk for pituitary dysfunction (eg, diabetes insipidus). Can be seen with
Patau syndrome (trisomy 13).
Monoventricle MRI reveals monoventricle A and fusion of basal ganglia (star in A ).
Lissencephaly Failure of neuronal migration resulting in a “smooth brain” that lacks sulci and gyri. May be
associated with microcephaly, ventriculomegaly.
Compare Results
New File:
Old File:
First Aid for the USMLE Step 1 2020, Thirtieth
FA 2019.pdf
versus edition-1.pdf
64 pages (293.11 MB)
64 pages (109.99 MB)
1/5/20, 12:57:57 PM
1/5/20, 12:52:18 PM
BY u/verified-idiot
To the only girl i've ever loved, to soufia.
BLUE new in FA 2020
YELLOW text of FA 2019 was edited; the note box next to the yellow highlight will show
the difference between them the old text and the new text of FA 2020
Some pages might look scary! because of note boxes and highlighting , but it is not, my
recommendation for you is to study your book and after than look for the new stuff and
edits.. I DONT recommend comparing while you are studying since it will consume your
time.
Go to First Change (page 1)
file://NoURLProvided[1/6/20, 3:42:22 PM]
,HIGH-YIELD SYSTEMS
Neurology and
Special Senses
“We are all now connected by the Internet, like neurons in a giant brain.” ` Embryology 490
—Stephen Hawking
` Anatomy and
“Anything’s possible if you’ve got enough nerve.” Physiology 493
—J.K. Rowling, Harry Potter and the Order of the Phoenix
` Pathology 511
“I like nonsense; it wakes up the brain cells.”
—Dr. Seuss ` Otology 533
“I believe in an open mind, but not so open that your brains fall out.”
` Ophthalmology 534
—Arthur Hays Sulzberger
“The chief function of the body is to carry the brain around.” ` Pharmacology 544
—Thomas Edison
“Exactly how [the brain] operates remains one of the biggest unsolved
mysteries, and it seems the more we probe its secrets, the more surprises we
find.”
—Neil deGrasse Tyson
Understand the difference between upper motor neuron (UMN) and
lower motor neuron (LMN) findings and the underlying anatomy.
Know the major motor, sensory, cerebellar and visual pathways and their
respective locations in the CNS. Connect key neurological associations
with certain pathologies (eg, cerebellar lesions, stroke manifestations,
Brown-Séquard syndrome). Recognize common findings on MRI/
CT (eg, ischemic and hemorrhagic stroke) and on neuropathology
(eg, neurofibrillary tangles and Lewy bodies). High-yield medications
include those used to treat epilepsy, Parkinson disease, migraine, and
pain (eg, opioids).
489
,490 SEC TION III NEUROLOGY AND SPECIAL SENSES `ǸEUROLOGY—EMBRYOLOGY
``
NEUROLOGY—EMBRYOLOGY
Neural development Notochord induces overlying ectoderm to differentiate into neuroectoderm and form neural plate.
Neural plate Neural plate gives rise to neural tube and neural crest cells.
Day 18 Notochord becomes nucleus pulposus of intervertebral disc in adults.
Notochord
Neural fold Alar plate (dorsal): sensory; regulated by TGF-β
(including bone morphogenetic protein [BMP])
Same orientation as spinal cord
Basal plate (ventral): motor; regulated by
Neural tube
Neural sonic hedgehog gene (SHH)
crest
cells
Day 21
Regional specification Telencephalon is the 1st part. Diencephalon is the 2nd part. The rest are arranged alphabetically:
of developing brain mesencephalon, metencephalon, myelencephalon.
Three primary Five secondary Adult derivatives of:
vesicles vesicles Walls Cavities
Telencephalon Cerebral Lateral
Wall Cavity hemispheres ventricles
Basal ganglia
Forebrain Diencephalon Thalamus Third
(prosencephalon) Hypothalamus ventricle
Retina
Midbrain Mesencephalon Midbrain Cerebral
(mesencephalon) aqueduct
Pons Upper part of
fourth ventricle
Metencephalon
Hindbrain Cerebellum
(rhombencephalon)
Myelencephalon
Medulla Lower part of
fourth ventricle
Spinal cord
Central and peripheral Neuroepithelia in neural tube—CNS neurons, ependymal cells (inner lining of ventricles, make
nervous systems CSF), oligodendrocytes, astrocytes.
origins Neural crest—PNS neurons, Schwann cells, glia, melanocytes, adrenal medulla.
Mesoderm—Microglia (like Macrophages).
, NEUROLOGY AND SPECIAL SENSES `ǸEUROLOGY—EMBRYOLOGY SEC TION III 491
Neural tube defects Neuropores fail to fuse (4th week) persistent connection between amniotic cavity and spinal
canal. Associated with maternal diabetes and folate deficiency. α-fetoprotein (AFP) in amniotic
fluid and maternal serum (except spina bifida occulta = normal AFP). acetylcholinesterase
(AChE) in amniotic fluid is a helpful confirmatory test.
Spina bifida occulta Failure of caudal neuropore to close, but no herniation. Usually seen at lower vertebral levels. Dura
is intact. Associated with tuft of hair or skin dimple at level of bony defect.
Meningocele Meninges (but no neural tissue) herniate through bony defect.
Myelomeningocele Meninges and neural tissue (eg, cauda equina) herniate through bony defect.
Myeloschisis Also called rachischisis. Exposed, unfused neural tissue without skin/meningeal covering.
Anencephaly Failure of rostral neuropore to close no forebrain, open calvarium. Clinical findings:
polyhydramnios (no swallowing center in brain).
+/ Tuft of hair Skin defect/thinning Skin thin or absent
Skin +/ Skin dimple
Subarachnoid
space
Dura
Leptomeninges
Spinal Transverse
cord process
Normal Spina bifida occulta Meningocele Myelomeningocele
Holoprosencephaly Failure of the embryonic forebrain (prosencephalon) to separate into 2 cerebral hemispheres;
A
usually occurs during weeks 5–6. May be related to mutations in sonic hedgehog signaling
pathway. Associated with other midline defects including cleft lip/palate (moderate form) and
★ cyclopia (severe form). risk for pituitary dysfunction (eg, diabetes insipidus). Can be seen with
Patau syndrome (trisomy 13).
Monoventricle MRI reveals monoventricle A and fusion of basal ganglia (star in A ).
Lissencephaly Failure of neuronal migration resulting in a “smooth brain” that lacks sulci and gyri. May be
associated with microcephaly, ventriculomegaly.
